2-(Trifluoromethyl)-4H-pyran-4-ones: Convenient, available and versatile building-blocks for regioselective syntheses of trifluoromethylated organic compounds

Abstract:

This review describes synthetic methods for the preparation of such modern and versatile building-blocks as 2-CF<inf>3</inf>-4-pyrones (2-(trifluoromethyl)-4H-pyran-4-ones), and their use in regioselective syntheses of various CF<inf>3</inf>-containing compounds. Synthesis of 2-CF<inf>3</inf>-4-pyrones bearing a substituent (substituents) at position(s) 3, 5 and 6, as well as regioselective preparation of trifluoromethylated 4(1H)-pyridin-4-one, benzo[c][1,6]naphthyridine, 4-thiopyrone, 2-quinaxolinone, diazepine, benzo[b][1,4]oxazin-2-one, pyrazole, 3-(pyrazolyl)indlole, pyrazolo[1,5-c]pyrimidine derivatives on the basis of these building-blocks has been described. The closest analogs of 2-CF<inf>3</inf>-4-pyrones, 2-R^F-4-pyrones (R^F = CF<inf>2</inf>H, C<inf>2</inf>F<inf>4</inf>H, C<inf>3</inf>F<inf>7</inf>, C<inf>4</inf>F<inf>9</inf>, C<inf>6</inf>F<inf>13</inf>, CF<inf>2</inf>CFCl<inf>2</inf>, CF<inf>2</inf>CHFCF<inf>3</inf>) has also been presented in the review. Due to unique regioselectivity, a strong regio-sensitivity to solvents and availability, 2-CF<inf>3</inf>-4-pyrones can be attributed to excellent starting or intermediate substrates for the preparation of various trifluoromethylated compounds. In contrast to other 2-R^F-4-pyrones, 2-CF<inf>3</inf>-4-pyrones are more synthetically available and interact with nucleophiles usually more selectively.

Año de publicación:

2015

Keywords:

• Solvent-sensitive reactions
• Advanced building-blocks
• regioselectivity
• 2-(Trifluoromethyl)-4-pyrones
• Trifluoromethylated heterocycles

Fuente:

scopus